Direct answer: what is a good Sharpe ratio in forex?
There is no single, universally accepted “good” Sharpe ratio for forex that you can apply to all markets and strategies. Any Sharpe ratio value is only meaningful relative to the way it was calculated (return frequency, risk/volatility definition, and the evaluation period) and to whether the result is robust out of sample.
Because forex outcomes can be sensitive to these choices, “good” typically means: high Sharpe for a reason other than chance and without obvious dependence on a narrow time window. If you want a more bounded way to think about performance quality, metrics that emphasize directional consistency—such as the Kaufman Efficiency Ratio—can help frame what “quality” looks like before assuming it will translate into risk-adjusted returns.
How Sharpe ratio works, and why a universal threshold fails
The Sharpe ratio is a risk-adjusted performance measure built from the relationship between average returns and the variability of those returns. In practice, different implementations can produce different values even for the same underlying trading idea because of:
- Return definition: log vs. arithmetic returns, and whether returns are computed per trade, per bar, or per day.
- Risk definition: what volatility measure is used, whether it is rolling, and how zero or near-zero variance periods are handled.
- Time window and sampling: a Sharpe over one month can differ greatly from a Sharpe over one year due to market regime changes.
- Costs and frictions: adding spreads, commissions, and slippage often reduces Sharpe, sometimes materially.
So, calling a specific number “good” without describing the calculation conditions is incomplete. Even “high” Sharpe can be misleading if achieved by a small set of trades, a favorable regime, or overfitting.
Within the Kaufman Efficiency Ratio scope, the key idea is to separate directional efficiency from risk-adjusted return. Kaufman Efficiency Ratio is a measure of how directly price moves from one point to another relative to the total distance traveled. When price movement is efficient (fewer reversals relative to net progress), strategies that depend on directional movement may have returns that are less noisy.
Example checks: how to judge whether a Sharpe ratio is meaningful
Instead of asking for a universal “good” number, you can apply checks that make the concept testable:
- Match the calculation setup: Compare Sharpe ratios computed with the same return frequency and the same volatility approach.
- Use multiple time windows: If Sharpe stays similar across different periods, it is more likely to reflect a stable property.
- Look for out-of-sample behavior: A Sharpe that appears only after selecting parameters is harder to trust.
- Cross-check with efficiency thinking: If directional movement is inconsistent (low efficiency in an efficiency-style sense), a Sharpe that looks high may be driven by unusual tail outcomes rather than stable movement.
As a cross-check, efficiency-style metrics (including Kaufman Efficiency Ratio) can be used to evaluate whether the underlying price behavior is characterized by relatively direct movement versus frequent back-and-forth. This does not guarantee future Sharpe, but it helps interpret whether the return stream is likely to be driven by persistent structure or randomness.
Limitations and risks
- No guaranteed interpretation: A Sharpe ratio is not a guarantee of future results; it summarizes historical variability and returns under specific assumptions.
- Sensitivity to assumptions: Small changes in how returns and risk are computed can change the Sharpe ratio.
- Chance and overfitting risk: Backtested Sharpe ratios can look good even when the strategy would perform worse in new data.
- Forex-specific complexity: Leverage, regime changes, and transaction costs can alter both returns and volatility, affecting Sharpe.